rpcgen(1)

an RPC protocol compiler

From the original Amiga UNIX 2.1 manual. Some things it mentions may not be in this release.

NAME

rpcgen - an RPC protocol compiler

SYNOPSIS

rpcgen infile
rpcgen [-Dname[=value]] [-T] [-K secs] infile
rpcgen -c|-h|-l|-m|-t [-o outfile ] infile
rpcgen -s nettype [-o outfile] infile
rpcgen -n netid [-o outfile] infile

DESCRIPTION

rpcgen is a tool that generates C code to implement  an  RPC
protocol.   The  input  to rpcgen is a language similar to C
known as RPC  Language  (Remote  Procedure  Call  Language).
rpcgen  is  normally  used as in the first synopsis where it
takes an input file and generates up to four  output  files.
If  the infile is named proto.x, then rpcgen will generate a
header  file  in  proto.h,  XDR  routines  in   proto_xdr.c,
server-side  stubs  in proto_svc.c, and client-side stubs in
proto_clnt.c.  With the -T option, it will also generate the
RPC  dispatch  table in proto_tbl.i.  The server created can
be started both by the port monitors (for example, inetd  or
listen) or by itself.  When it is started by a port monitor,
it creates servers only for the transport for which the file
descriptor  0 was passed.  The name of the transport must be
specified  by  setting   up   the   environmental   variable
PM_TRANSPORT.   When  the server generated by rpcgen is exe-
cuted, it creates server  handles  for  all  the  transports
specified  in  NETPATH  environment  variable,  or  if it is
unset, it creates server handles for all the  visible  tran-
sports  from /etc/netconfig file.  Note:  the transports are
chosen at run time and not at compile time.  When the server
is  self-started,  it backgrounds itself by default.  A spe-
cial define symbol RPC_SVC_FG can be used to run the  server
process in foreground.  The second synopsis provides special
features which allow for the creation of more  sophisticated
RPC  servers.   These features include support for user pro-
vided #defines and RPC dispatch tables.  The entries in  the
RPC dispatch table contain:
     •  pointers to the  service  routine  corresponding  to
        that procedure,
     •  a pointer to the input and output arguments
     •  the size of these routines
A server can use the dispatch table to  check  authorization
and  then  to  execute the service routine; a client library
may use it to deal with the details  of  storage  management
and  XDR  data  conversion.   The other three synopses shown
above are used when one does not want to  generate  all  the
output  files,  but only a particular one.  Some examples of
their usage is described in the EXAMPLE section below.  When
rpcgen  is  executed  with the -s option, it creates servers
for that particular class of transports.  When executed with
the  -n option, it creates a server for the transport speci-
fied by netid.  If infile is not specified,  rpcgen  accepts
the  standard input.  The C preprocessor, cc -E [see cc(1)],
is run on the input file before it is  actually  interpreted
by  rpcgen.   For each type of output file, rpcgen defines a
special preprocessor symbol for use by the  rpcgen  program-
mer:
RPC_HDR     defined when compiling into header files
RPC_XDR     defined when compiling into XDR routines
RPC_SVC     defined when compiling into server-side stubs
RPC_CLNT    defined when compiling into client-side stubs
RPC_TBL     defined when compiling into RPC dispatch  tables
            Any  line  beginning with `%' is passed directly
            into the output file, uninterpreted  by  rpcgen.
            For  every  data  type  referred  to  in infile,
            rpcgen assumes that there exists a routine  with
            the  string  xdr_  prepended  to the name of the
            data type.  If this routine does  not  exist  in
            the  RPC/XDR library, it must be provided.  Pro-
            viding an undefined data type allows  customiza-
            tion of XDR routines.
            The following options are available:

-c          Compile into XDR routines.

-Dname[=value]

Define a symbol name. Equivalent to the #define directive in the source. If no value is given, value is defined as 1. This option may be specified more than once.

-h Compile into C data-definitions (a header file). -T option can be used in conjunction to produce a header file which supports RPC dispatch tables.

-K secs By default, services created using rpcgen wait 120 seconds after servicing a request before exiting. That interval can be changed using the -K flag. To create a server that exits immediately upon servicing a request, -K 0 can be used. To create a server that never exits, the appropriate argument is -K -1.

When monitoring for a server, some portmonitors, like listen(1M), always spawn a new process in response to a service request. If it is known that a server will be used with such a monitor, the server should exit immediately on completion. For such servers, rpcgen should be used with -K -1.

-l Compile into client-side stubs.

-m Compile into server-side stubs, but do not generate a main routine. This option is useful for doing callback-routines and for users who need to write their own main routine to do initialization.

-n netid Compile into server-side stubs for the transport specified by netid. There should be an entry for netid in the netconfig database. This option may be specified more than once, so as to compile a server that serves multiple transports.

-o outfile Specify the name of the output file. If none is specified, standard output is used (-c, -h, -l, -m, -n, -s and -t modes only).

-s nettype Compile into server-side stubs for all the transports belonging to the class nettype. The supported classes are netpath, visible, circuit_n, circuit_v, datagram_n, datagram_v, tcp, and udp [see rpc(3N) for the meanings associated with these classes]. This option may be specified more than once. Note: the transports are chosen at run time and not at compile time.

-t Compile into RPC dispatch table.

-T Generate the code to support RPC dispatch tables. The options -c, -h, -l, -m, -s and -t are used exclusively to generate a particular type of file, while the options -D and -T are global and can be used with the other options.

NOTES

The RPC Language does not support nesting of structures. As a work-around, structures can be declared at the top-level, and their name used inside other structures in order to achieve the same effect. Name clashes can occur when using program definitions, since the apparent scoping does not really apply. Most of these can be avoided by giving unique names for programs, versions, procedures and types. The server code generated with -n option refers to the transport indicated by netid and hence is very site specific.

EXAMPLE

The following example:

$ rpcgen -T prot.x generates all the five files: prot.h, prot_clnt.c, prot_svc.c, prot_xdr.c and prot_tbl.i. The following example sends the C data-definitions (header file) to the standard output.

$ rpcgen -h prot.x To send the test version of the -DTEST, server side stubs for all the transport belonging to the class datagram_n to standard output, use:

$ rpcgen -s datagram_n -DTEST prot.x To create the server side stubs for the transport indicated by netid tcp, use: